package com.w4cms.utils;

import java.security.MessageDigest;
import java.util.Random;

import org.apache.commons.codec.binary.Hex;

public class PasswordUtil {
		/**
		 * 生成含有随机盐的密码
		 */
		public static String generate(String password) {
			int i1 = new Random().nextInt(99042999);
			int i2 = new Random().nextInt(99112599);
			String salt = String.valueOf(i1) + String.valueOf(i2);
			if (salt.length() < 16) {
				for (int i = 0; i < 16 - salt.length(); i++) {
					salt += "0";
				}
			}
			password = md5Hex(password + salt);
			char[] cs1 = password.toCharArray();
			char[] cs2 = salt.toCharArray();
			char[] cs = new char[48];
			for (int i = 0; i < 48; i += 3) {
				cs[i] = cs1[i / 3 * 2];
				cs[i + 1] = cs2[i / 3];
				cs[i + 2] = cs1[i / 3 * 2 + 1];
			}
			return new String(cs);
		}

		/**
		 * 校验密码是否正确
		 */
		public static boolean verify(String password, String md5) {
			char[] cs = md5.toCharArray();
			char[] cs1 = new char[32];
			char[] cs2 = new char[16];
			for (int i = 0; i < 48; i += 3) {
				cs1[i / 3 * 2] = cs[i];
				cs1[i / 3 * 2 + 1] = cs[i + 2];
				cs2[i / 3] = cs[i + 1];
			}
			String salt = new String(cs2);
			return md5Hex(password + salt).equals(new String(cs1));
		}

		/**
		 * 获取十六进制字符串形式的MD5摘要
		 */
		public static String md5Hex(String src) {
			try {
				MessageDigest md5 = MessageDigest.getInstance("MD5");
				byte[] bs = md5.digest(src.getBytes());
				return new String(new Hex().encode(bs));
			} catch (Exception e) {
				return null;
			}
		}

		public static void main(String[] args) {
			String password = generate("123456");
			System.out.println(password);
			System.out.println(verify("123456", "d52c4539bb6f12df23e7399127726f97ec1a997799619411"));
		}
}
